It is generally known to a person skilled in the art of antifriction bearing technology that single-row grooved ball bearings represent a classic form of rigid radial antifriction bearings which cannot be dismantled, have deep grooves configured with a radius a little larger than the ball radius and are distinguished above all by the fact that their radial and axial loadbearing capability is equally high and that they have the highest speed limits of all bearing types on account of their low friction. In contrast, single-row angular contact ball bearings are a further form of radial antifriction bearings which can or cannot be dismantled, since their raceways are arranged in such a way that the forces which occur are transmitted from one raceway to the other at a defined contact angle obliquely with respect to the radial plane. However, on account of their contact angle, angular contact ball bearings are better suited to absorbing higher axial forces than grooved ball bearings, it being possible for radial forces to be transmitted by single-row angular contact ball bearings only if they are loaded axially at the same time. These single-row grooved ball bearings and angular contact ball bearings have been known for a long time and comprise substantially an outer bearing ring and inner bearing ring and a multiplicity of balls as rolling bodies which are arranged between the bearing rings. Ball raceways which are delimited by one or two shoulders, each of which are machined into the inner side of the outer bearing ring and into the outer side of the inner bearing ring, in which ball raceways the balls roll by way of their running faces and are guided at uniform spacings from one another by a bearing cage.
In grooved ball bearings or angular contact ball bearings of this type, the necessarily different configuration of the raceway radii in comparison with the ball radii has proven disadvantageous, however, to the extent that the bearing balls are only in punctiform contact with their raceway in the inner bearing ring as a result and therefore cause a high surface pressure on the raceway in the region of the contact angle axis, which high surface pressure is responsible for increased wear of said raceway. In addition, high edge stresses occur in the region of the shoulder edge/edges of the raceway as a result of the bearing balls which overlap said shoulder edge/edges in the case of normal osculation but bear against the shoulder edge/edges after the osculation has been used up, as a result of which high edge stresses the wear of the raceway for the bearing balls is increased still further and the service life of grooved ball bearings or angular contact ball bearings of this type is reduced considerably.
One possibility of avoiding the high surface pressure on the raceway of the inner bearing ring in the region of the contact angle axis of the rolling bodies has been disclosed in DE 43 34 195 A1. In the radial antifriction bearings which are disclosed in said document and are configured per se as single-row grooved ball bearing or angular contact ball bearing, however, the rolling bodies are not formed by balls but rather either partially or completely by what are known as spherical disks which are configured with two side faces which are flattened symmetrically from a basic spherical shape and are arranged parallel to one another. The width of these spherical disks between their side faces is configured to be smaller than the spacing between the inner side of the outer bearing ring and the outer side of the inner bearing ring, with the result that, when the bearing is filled, the spherical disks can be inserted into the bearing axially with respect to the bearing through the spacing between the inner ring and the outer ring and can be rotated into the raceway. Since the spherical disks have a constant rotational axis in contrast to conventional bearing balls, the running faces of the spherical disks are configured with the same radius as their raceways in the bearing rings, with the result that the spherical disks are in linear contact with the raceways. As a result of this linear contact, instead of the disadvantageous punctiform contact which occurs in single-row grooved ball bearings or angular contact ball bearings, a situation is achieved where a uniform surface pressure with a low stress level occurs between the spherical disks and the raceways.
However, it has been shown in operation and under load that, in grooved antifriction bearings or angular contact antifriction bearings of this type with spherical disks as rolling bodies, as a result of the fact that the raceways in the bearing rings are of wider configuration than the spherical disks, the spherical disks cause high edge stresses at the outer edge regions of the raceway in the inner bearing ring by way of their edge parts which adjoin their straight side faces, which high edge stresses are still responsible for increased wear of this raceway and therefore reduce the service life of grooved antifriction bearings or angular contact antifriction bearings of this type.